This Computer boasts a 733Mhz Motorola PowerPC G4 CPU, though not fast enough to run leopard natively, it runs 10.4.11 "Tiger" fine.

It has a 733Mhz Motorola PowerPC 7450 (G4).

Start by removing the heatsink clamps with a flathead screwdriver.

Do the same for the other side.

Then Lift off the heatsink.

This will reveal the CPU.

Remove these screws.